How do I amend a previous year, if I did not file with turbo tax? 2017

[Leonard]

You can use TurboTax to file your amended 2017 tax return using  Form 1040X even if you did not file the original tax return using TurboTax.  The link below has information that you may find useful.

[mesquitebean]

@TurboTaxLeonard
The link you were going to include in your Answer above is missing.  I presume it is a FAQ for this situation, but I can't find it.

@szlide
You may wish to get it amended wherever you originally filed the return, and it might be easier.

You can do it with TurboTax, but it is not easy since your original return was not prepared with TurboTax.   You can purchase the 2017 TurboTax software to install on your computer.  You can buy it here:
<a rel="nofollow" target="_blank" href="https://turbotax.intuit.com/personal-taxes/past-years-products/">https://turbotax.intuit.com/persona...>

Then you have to re-create your 2017 Federal return exactly as it was originally filed (and State return, if applicable).
Once the Federal return is re-created, then you have to fool TurboTax by telling it you want to file the returns by mail (of course, you don't really file them, since you already have.)  But you have to say that to TurboTax software, otherwise the program won't let you amend the returns.
But once TurboTax thinks you have filed it, then it will let you amend it.

The amended return Form 1040X and any changed forms cannot be efiled.  It has to be printed, signed, dated, and mailed.   It can take the IRS up to 16 weeks to process an amended return.

If you amend the Federal return, you likely have to amend your state return as well (if applicable.)

Depending on what you need to amend, it might be easier to just download the Form 1040X and Instructions at the IRS website and prepare it by hand like in the "old days."
<a rel="nofollow" target="_blank" href="https://www.irs.gov/forms-instructions">https://www.irs.gov/forms-instructions</a>

[yak5yak5]

My computer crashed and I lost all previous years information.  I am now completing my business Form 1120 for 2018 but need to enter previous years information from my hard copy of last years return(1120 for 2017).  How do I do this?

[Critter]

You have 2 options ... 

1) reinstall the 2017 program, recreate the 2017 return then transfer that info to the 2018 program

2) complete the 2018 return and enter info from the 2017 return as needed like in the asset section ... this will not get a side by side screen comparison filled in but it will  suffice for the return. 

[Critter]

Always  save a PDF and .taxfile of ALL your returns on at least one removable storage medium to safeguard your returns against just this sort of incident.